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Nautilus Interconnector

Nautilus Interconnector is a proposed Multi-Purpose Interconnector between Great Britain and Belgium. The project will have the capability to connect to multiple offshore wind farms, helping to create a cleaner, smarter energy system.

What is Nautilus Interconnector?

Nautilus Interconnector is a proposed Multi-Purpose Interconnector (MPI) connection between Great Britain and Belgium that will provide enough electricity to supply around 1.4 million UK homes.

When built, Nautilus will unlock 1.4 gigawatt (GW) of offshore wind and connect this to the transmission systems of Great Britain and Belgium through a high voltage direct current (HVDC) electricity link. Nautilus will include underground cabling works and onshore infrastructure which will be located in East Suffolk.


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The next generation of interconnector

Electricity interconnectors are the perfect tool to deliver a cleaner, more secure and more affordable energy system for consumers.

They play a vital role in delivering secure, affordable energy between markets. By transporting renewable electricity from where it is produced to where it’s consumed, they are helping to create a cleaner, smarter energy system.

Instead of individual wind farms connecting one by one to the shore, MPIs would allow clusters of offshore wind farms to connect all in one go, plugging into the energy system of the UK and neighbouring countries.

At present, offshore wind and interconnectors operate alongside each other. In the future, MPIs will enable offshore wind and interconnection to work together as a combined asset. Helping to:

  • Support UK efforts to meet 2030 and 2050 climate targets
  • Reduce impact on coastal communities with fewer individual connections and less construction needed
  • Enable a reliable flow of electricity that can be turned up or down when needed
  • Generate a greater proportion of electricity from the North Sea via offshore wind
  • Provide significant environmental and cost reductions by using shared assets and clusters of connections

Read more about how MPIs could help Great Britain unlock the potential of offshore wind

About the project

Electricity provided by Nautilus will be transported under the North Sea via high voltage subsea cables which will be buried underground onshore at a point known as ‘landfall’ before connecting into an onshore converter station and then via a substation, to the National Transmission System. Options for the underground onshore cable route, landfall and converter station on the East Suffolk Coast are currently being assessed for feasibility.

In October 2020, Nautilus was reclassified as an MPI, a new generation of Interconnector which will have the capability to connect to multiple offshore wind farms, enabling the export of excess clean energy and reducing the impact of infrastructure on coastal communities. 

Nautilus is currently at a very early stage of its development. Should the project be progressed, a rigorous Environmental Impact Assessment (EIA) and pre-application consultation process will take place and a final application for a Development Consent Order (DCO) could be submitted in 2023. Should consent be granted, a Final Investment Decision is planned for 2024/25. Following this, construction would commence, and the project could be operational by 2028.

Indicative timeline

Please note that all dates are indicative and subject to change.


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The planning process

Nautilus Interconnector has been classified as a Nationally Significant Infrastructure Project (NSIP) in the UK and a Project of Common Interest (PCI) in Europe. As part of the NSIP process, the project has a live page on the Planning Inspectorate’s website.

Nationally Significant Infrastructure Project (NSIP)

Nautilus Interconnector is classified as a Nationally Significant Infrastructure Project (NSIP) by the Secretary of State for Business, Energy and Industrial Strategy (BEIS). The development will be required to submit an application for a Development Consent Order (DCO) where a final decision whether to grant consent will be made by the Secretary of State for BEIS.

The DCO regime requires a robust Environmental Impact Assessment and pre-application consultation process prior to any application being submitted. The DCO consent process will provide a single, unified consenting process with clear and fixed timescales.

Project of Common Interest (PCI)

PCIs are key cross border infrastructure projects that link the energy systems of countries in Europe. They are intended to help Europe achieve its energy and climate objectives: affordable, secure and sustainable energy for all citizens. In the long-term, PCIs are also aimed at realising the decarbonisation of the economy in accordance with the Paris Agreement signed by the UK, which aims to achieve climate neutrality by the end of the century.

In the case of Nautilus Interconnector, the project has been identified as a PCI due to its significant impact on the energy market and market integration between the UK and Belgium. The project will boost competition in the energy market, achieve energy security from a more diverse supply and contribute to our climate and energy goals. The selection process for PCI projects is determined by the Trans-European Networks for Energy (TEN-E) Regulation, which will be complied with throughout the development process for Nautilus.


Environmental Impact Assessment (EIA) process

Extensive environmental surveys and studies will be undertaken for Nautilus Interconnector as part of the Environmental Impact Assessment (EIA process) and a range of statutory consultees and stakeholders will be consulted with. As part of this process, a Scoping Report, a Preliminary Environmental Information Report (PEIR) and an Environmental Statement (ES) will be produced.

Scoping Report

A Scoping Report will be submitted to the Planning Inspectorate. This will present the proposals for the Nautilus Interconnector and will describe how any potential impacts to the existing environment will be assessed. The feedback received on this document from the local planning authorities and statutory consultees will result in a Scoping Opinion from the Planning Inspectorate, which will be made publicly available.

Preliminary Environmental Information Report (PEIR)

The PEIR will build upon the findings from the earlier scoping documents, as well as the feedback received through consultation. It will incorporate the findings of the surveys and environmental assessments that have been carried out. This will enable consultees to develop an informed view of the potential impacts Nautilus may have on the local environment.

Environmental Statement (ES)

The ES will advance the content of the PEIR and will incorporate the responses from the consultation and the results of the surveys undertaken. It will also describe any changes to the project and any mitigation measures proposed to be implemented. The ES will form part of the DCO application for submission.

Copies of these reports will be made available during the public consultation. Options and ideas will be presented to consultees and environmental authorities as the proposals develop to understand the best approach for the final proposals.

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